Emerging Enterococcus gallinarum infections and its antibiotic resistance in Karachi, Pakistan

Abstract

This is the first report about the prevalence and the antibiotic resistance of the emerging pathogen E. gallinarum from Karachi, Pakistan. A total of 156 different clinical samples were collected from pathological laboratories and hospitals during April 2012 to 2014. E. gallinarum strains were identified by latex agglutination kit (Oxoid) and ABIS software online. Their resistance against seventeen antibiotics was determined by Kirby-Bauer disc diffusion method. Minimum inhibitory concentration (MIC) of vancomycin, macrolides (azithromycin, clarithromycin), clindamycin, ciprofloxacin and cefotaxime were determined by broth dilution method. In this study 51 E. gallinarum strains were isolated from 156 clinical samples. Maximum number of isolates was obtained from throat swab 29 (58%) followed by pus samples 16 (31%). E. gallinarum infections predominantly occurred during the cool season of the year. All E. gallinarum were resistant against streptomycin while sensitive to teicoplanin, imipenem, ampicillin and fosfomycin. More than half of the isolates were resistant against clindamycin, macrolides, penicillin, cefotaxime and ciprofloxacin, however the resistance against vancomycin and gentamycin was 40%. Over all the isolates from pus were more resistant than isolates from throat swabs. This report highlights a high level of resistance to a number of antibiotics making E. gallinarum an important emerging pathogen.